Japan observed a moment of silence Saturday as it marked the sixth anniversary of a killer tsunami triggered by the massive March 11, 2011, earthquake that left more than 20,000 dead or unaccounted for and 120,000 still displaced.

A solemn atmosphere took hold of the hardest-hit northeastern prefectures of Iwate, Miyagi and Fukushima at 2:46 p.m., as the nation offered silent prayers to those who perished in the biggest natural calamity in Japan’s postwar history, a disaster that devastated large swaths of the Tohoku region.

The death toll from the magnitude-9 quake and ensuing tsunami — plus numerous aftershocks in the months following — had reached 15,893 as of Friday, according to National Police Agency statistics.

That figure would be higher when combined with deaths triggered by stress and illness stemming from the disaster, which the reconstruction ministry put at 3,523 as of last September.

The latest NPA statistics also show that 2,553 people are still unaccounted for, which could further boost the death toll.

On top of this, 123,168 other people remain displaced, including 39,598 who fled Fukushima in the wake of nuclear meltdowns at Fukushima No. 1 power plant — the world’s worst nuclear crisis since the 1986 Chernobyl accident in Ukraine, the reconstruction ministry said.

These evacuees are forced to live “uncomfortable” lives in places such as temporary housing facilities and hospitals, Prime Minister Shinzo Abe noted in a speech delivered during an annual memorial ceremony organized by the government in Tokyo.

Abe said he is “overwhelmed even now with deep sorrow” at the thought of victims and their bereaved families and extended his “heartfelt sympathies to all those who have been affected by the disaster.”

Nevertheless, the nation’s leader took the opportunity to emphasize that the government has made significant headway in rebuilding the areas and revitalizing regional economies, while also reaffirming Japan’s commitment to beefing up its “international contributions” in the field of disaster prevention.

Six years on, “I feel that reconstruction is steadily making progress,” he said.

“Restoration of infrastructure is nearly complete, while the rebuilding of homes and the revitalization of industries and livelihoods is proceeding step by step.”

The reconstruction ministry says the agricultural and fishery businesses of the three hardest-hit prefectures have “almost recovered” to pre-quake levels, with 83 percent of farmland deemed ready for planting and 91 percent of seafood processing facilities having resumed operations.

Abe then added it is Japan’s responsibility to share with the rest of the world the lessons it learned from the Great East Japan Earthquake — as the quake and tsunami are called, referring to its “disaster prevention knowledge and technology that can be instrumental in minimizing future calamities.”

Similar memorial events hosted by local municipalities were held nationwide.

Also present at the nationally televised memorial service in Tokyo was Prince Akishino, who echoed Abe’s praise for the steady progress in reconstruction efforts but at the same time elaborated on a heartache he feels at the predicament of many still stuck in limbo.

“My heart aches deeply when thinking about the health of the elderly” and “feelings of evacuees from high-radiation dose areas where the prospects of returning to their own homes are still dim,” he said.

Yoshinobu Ishii, a Fukushima survivor who made a speech at the event, said that while an evacuation order for his home village of Kawauchi has been entirely lifted, the place has become almost unrecognizable.

“The village is far from what it used to be as there are many issues that remain to be overcome,” said Ishii, 72, who lost his ailing mother in the disaster.

He said few of the younger residents who fled the village have shown any willingness to return due to concern over their children’s education, further depopulating the community.

On Friday, a government council on reconstruction decided to partially lift an evacuation order for the towns of Namie and Tomioka, both located in the vicinity of the crippled Fukushima No. 1 plant, on March 31 and April 1, respectively.

The latest move, however, will still leave the better part of Namie designated as an area “difficult to return home to” due to relatively high levels of remaining radioactive fallout.